Silver halide photographic light-sensitive material

Abstract

A silver halide photographic light-sensitive material comprising a specific silver halide grain is disclosed. The siliver halide grain contains a localized portion containing 20 mol % or more of silver iodide and average content of silver iodide of which grain is from 0.1 to 10.0 mol %, provided that the silver halide grain is prepared by mixing an aqueous solution containing a water soluble halide compound and an aqueous solution containing a water soluble silver salt under a condition that pAg of the mixture is raised at 9.7 or more during a period after a half amount of the silver salt to be used has been added to the mixture. The photographic light-sensitive material has improved photographic characteristics and is suitable for radiographic use.

What is claimed is: 
     
       1. A silver halide photographic light-sensitive material, comprising a support and at least one silver halide photographic emulsion layer provided on said support, said at least one silver halide emulsion layer containing a silver halide grain which has a localized portion containing 20 mol% or more silver iodide and average silver iodide content of which grain is from 0.1 to 10 mol%, provided that said silver halide grain is prepared by mixing an aqueous solution containing a water soluble halide compound and an aqueous solution containing a water soluble silver salt under a condition that pAg of the mixture is raised between 9.7 and 12.5 during a period after a half amount of said silver salt to be used has been added to the mixture. 
     
     
       2. The light-sensitive material of claim 1, wherein pAg of said mixture is raised during a period between a point when a half amount of said water soluble silver salt is added and the point when 9/10 of said water soluble silver salt is added to the mixture, and pAg of the mixture at the point when the mixing is completed is between 9.7 and 12.5. 
     
     
       3. The light-sensitive material of claim 2, wherein raising of pAg is carried out continuously or stepwise. 
     
     
       4. The light-sensitive material of claim 1, wherein at least 50% by weight of the total silver halide grains contained in said silver halide emulsion layer is said silver halide grain. 
     
     
       5. The light-sensitive material of claim 1, wherein said silver halide emulsion layer contains a compound represented by the general formula [I], [II] or [III]: ##STR30## wherein R 1 , R 2  and R 3  are independently selected from a substituted or unsubstituted alkyl, alkenyl and aryl group and at least one of R 1  and R 3  is a sulfoalkyl or carboxyalkyl group, X 1   -  is an anion, Z 1  and Z 2  independently represent a group of nonmetallic atoms necessary to complete a substituted or unsubstituted benzene ring and n represents an integer 1 or 2, provided that when said compound forms an intramolecular salt, n is 1, ##STR31## wherein R 4  and R 5  are independently selected from a substituted or unsubstituted alkyl, alkenyl and aryl group and at least one of them is a sulfoalkyl or carboxyalkyl group, R 6  is selected from a hydrogen atom, a lower alkyl and aryl group, X 2   -  is an anion, Z 1 , Z 2  and n are respectively the same as defined in the general formula [I], ##STR32## wherein R 7  and R 8  are independently selected from a substituted or unsubstituted lower alkyl group, R 9  and R 10  are independently selected from a lower alkyl, hydroxylalkyl, sulfoalkyl and carboxyalkyl group, X 3   -  is an anion, Z 1 , Z 2  and n are respectively the same as defined in the general formula [I]. 
     
     
       6. The light-sensitive material of claim 1, wherein said silver halide grain is sensitized with from 1.0×10 -16  to 1.0×10 -20  mol of a gold sensitizer per μm 2  of the surface area of said silver halide grain. 
     
     
       7. The light-sensitive material of claim 1, wherein γ of the line connecting the points respectively corresponding 0.05 and 0.30 of optical density on the characteristic curve of said light-sensitive material (γ 1 ) and γ of the line connecting the points respectively corresponding 0.50 and 1.50 of optical density on said characteristic curve, of said light-sensitive material (γ 2 ) are from 0.5 to 1.0 and from 2.50 to 3.50, respectively, provided that said light-sensitive material is exposed and developed with the following treatment, and the D- Log E characteristic curve is drawn on rectangular coodinates in which optical density D and exposure-amount log E are graduated in the same unit length on each axes:   ______________________________________                                    
treating       temperature                                                
                          time                                            
______________________________________                                    
developing     35° C.                                              
                          35 sec.                                         
fixing         34° C.                                              
                          20 sec.                                         
washing        33° C.                                              
                          18 sec.                                         
drying         45° C.                                              
                          22 sec.                                         
______________________________________                                    
[Developer]                                                               
______________________________________                                    
Potassium sulfite      55.5   g                                           
Hydroquinone           25.0   g                                           
1-phenyl-3-pyrazolidone                                                   
                       1.2    g                                           
Boric acid             10.0   g                                           
Potassium hydroxide    21.0   g                                           
Triethylene glycol     17.5   g                                           
5-methylbenzotriazole  0.04   g                                           
5-nitrobenzimidazole   0.11   g                                           
1-phenyl-5-mercaptotetrazole                                              
                       0.015  g                                           
Glutaraldehyde bisulfite                                                  
                       15.5   g                                           
Glacial acetic acid    16.0   g                                           
Add water to make      1000   ml.                                         
______________________________________